In the fuel injection systems set forth in U.S. Pat. No. 5,070,845 issued Dec. 10, 1991 in the name of Advenko et al. and in U.S. Pat. No. 5,082,184 issued Jan. 21, 1992 in the name of Stettner et al., a single injector meters fuel which is distributed to a plurality of fuel lines having nozzle terminations. The nozzles discharge fuel adjacent the engine intake ports. Such a system has, as a principle feature or benefit, the localization of fuel metering components in a single fuel metering body which can be located inside of the intake manifold. The use of a single injector dictates that each nozzle and, as a result, each cylinder be fueled simultaneously, without regard to cylinder timing. The result is less than optimal engine and emission performance. In addition, the location of the fuel meter body within the intake manifold proliferates the connective hardware required for fuel and electric to pass through the wall of the manifold.
In the fuel injection systems set forth in U.S. Pat. No. 4,510,909 issued Apr. 16, 1985 in the name of Elphick et al. and in U.S. Pat. No. 4,586,477 issued May 6, 1986 in the name of Field et al., fuel rails deliver fuel to a plurality of outwardly extending electromagnetic fuel injectors. The rail-injector assembly is secured to the exterior of the intake manifold of an engine with the injectors received in openings therein for delivery of fuel to associated engine cylinders. The use of individual injectors for each cylinder permits optimization of the fueling event. The location of the fuel rail and its relatively large surface area may cause fuel passing through the rail to be subjected to significant heating, increasing the likelihood of hot fuel handling problems and running loss emissions. Fuel rails are application specific, and a separate rail must be designed for each engine. In addition, the electromagnetic injectors used in such systems have relatively large diameters resulting from the placement of the solenoid in the point-of-delivery device. As such, significant limitations are placed on injector location and fuel targeting.